SEMICONDUCTOR MEMORY DEVICE
A semiconductor memory device includes a plurality of word lines, a first select gate line, a second select gate line, a first semiconductor layer, a third select gate line, a fourth select gate line, a second semiconductor layer, and a word line contact electrode. The first select gate line and the third select gate line are farther from the substrate than the plurality of word lines. The second select gate line and the fourth select gate line are closer to the substrate than the plurality of word lines. The first semiconductor layer is opposed to the plurality of word lines, the first select gate line, and the second select gate line. The second semiconductor layer is opposed to the plurality of word lines, the third select gate line, and the fourth select gate line. The word line contact electrode is connected to one of the plurality of word lines.
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This application is based upon and claims the benefit of Japanese Patent Application No. 2021-133721, filed on Aug. 18, 2021, the entire contents of which are incorporated herein by reference.
BACKGROUND FieldEmbodiments described herein relate generally to a semiconductor memory device.
Description of the Related ArtThere has been known a semiconductor memory device that includes a substrate, a plurality of word lines stacked in a direction intersecting with a surface of this substrate, a semiconductor layer opposed to these plurality of word lines, and a gate insulating layer disposed between the word lines and the semiconductor layer. The gate insulating layer includes a memory unit that can store data, and the memory unit is, for example, an insulating electric charge accumulating layer of, for example, silicon nitride (Si3N4), or a conductive electric charge accumulating layer, such as a floating gate.
A semiconductor memory device according to one embodiment includes a substrate, a plurality of word lines, a first select gate line, a second select gate line, a first semiconductor layer, a first bit line, a third select gate line, a fourth select gate line, a second semiconductor layer, a second bit line, and a word line contact electrode. The substrate includes a first region and a second region arranged in a first direction and a third region disposed between the first region and the second region. The plurality of word lines extend in the first direction across the first region, the second region, and the third region. The plurality of word lines are arranged in a second direction intersecting with the first direction. The first select gate line is disposed in the first region and farther from the substrate than the plurality of word lines. The second select gate line is disposed in the first region and closer to the substrate than the plurality of word lines. The first semiconductor layer is disposed in the first region. The first semiconductor layer extends in the second direction and is opposed to the plurality of word lines, the first select gate line, and the second select gate line. The first bit line extends in a third direction intersecting with the first direction and the second direction. The first bit line is disposed at a position overlapping with the first semiconductor layer viewed in the second direction. The third select gate line is disposed in the second region and farther from the substrate than the plurality of word lines. The fourth select gate line is disposed in the second region and closer to the substrate than the plurality of word lines. The second semiconductor layer is disposed in the second region. The second semiconductor layer extends in the second direction and is opposed to the plurality of word lines, the third select gate line, and the fourth select gate line. The second bit line extends in the third direction. The second bit line is disposed at a position overlapping with the second semiconductor layer viewed in the second direction. The word line contact electrode is disposed in the third region. The word line contact electrode extends in the second direction and is connected to one of the plurality of word lines.
Next, the semiconductor memory devices according to embodiments are described in detail with reference to the drawings. The following embodiments are only examples, and not described for the purpose of limiting the present invention. The following drawings are schematic, and for convenience of description, a part of a configuration and the like is sometimes omitted. Parts common in a plurality of embodiments are attached by same reference numerals and their descriptions may be omitted.
In this specification, when referring to a “semiconductor memory device”, it may mean a memory die and may mean a memory system including a controller die, such as a memory chip, a memory card, and a Solid State Drive (SSD). Further, it may mean a configuration including a host computer, such as a smartphone, a tablet terminal, and a personal computer.
A “control circuit” in this specification may mean a peripheral circuit, such as a sequencer, disposed in a memory die, may mean a controller die, a controller chip, or the like connected to a memory die, and may mean a configuration including both of them.
In this specification, when it is referred that a first configuration “is electrically connected” to a second configuration, the first configuration may be directly connected to the second configuration, or the first configuration may be connected to the second configuration via a wiring, a semiconductor member, a transistor, or the like. For example, when three transistors are connected in series, even when the second transistor is in OFF state, the first transistor is “electrically connected” to the third transistor.
In this specification, when it is referred that the first configuration “is connected between” the second configuration and a third configuration, it may mean that the first configuration, the second configuration, and the third configuration are connected in series and the second configuration is connected to the third configuration via the first configuration.
In this specification, when it is referred that a circuit or the like “electrically conducts” two wirings or the like, it may mean, for example, that this circuit or the like includes a transistor or the like, this transistor or the like is disposed in a current path between the two wirings, and this transistor or the like is turned ON.
In this specification, a direction parallel to an upper surface of the substrate is referred to as an X-direction, a direction parallel to the upper surface of the substrate and perpendicular to the X-direction is referred to as a Y-direction, and a direction perpendicular to the upper surface of the substrate is referred to as a Z-direction.
In this specification, a direction along a predetermined plane may be referred to as a first direction, a direction along this predetermined plane and intersecting with the first direction may be referred to as a second direction, and a direction intersecting with this predetermined plane may be referred to as a third direction. These first direction, second direction, and third direction may each correspond to any of the X-direction, the Y-direction, and the Z-direction and need not correspond to these directions.
Expressions such as “above” and “below” in this specification are based on the substrate. For example, a direction away from the substrate along the Z-direction is referred to as above and a direction approaching the substrate along the Z-direction is referred to as below. A lower surface and a lower end of a certain configuration mean a surface and an end portion at the substrate side of this configuration. An upper surface and an upper end of a certain configuration mean a surface and an end portion at a side opposite to the substrate of this configuration. A surface intersecting with the X-direction or the Y-direction is referred to as a side surface and the like.
First Embodiment Memory System 10The memory system 10 performs a read operation, a write operation, an erase operation, and the like of user data according to signals transmitted from a host computer 20. The memory system 10 is, for example, any system that can store the user data including a memory chip, a memory card, and an SSD. The memory system 10 includes a plurality of memory dies MD and a controller die CD. The memory die MD stores the user data. The controller die CD is connected to the plurality of memory dies MD and the host computer 20. The controller die CD includes, for example, a processor and a RAM. The controller die CD performs processes, such as conversion between a logical address and a physical address, bit error detection/correction, a garbage collection (compaction), and a wear leveling.
As illustrated in
As illustrated in
Note that the configurations illustrated in
Note that
As illustrated in
As illustrated in
For example, as illustrated in
The memory string MS includes drain-side select transistors STDT and STD, dummy memory cells DMC5 to DMC3, a plurality of memory cells MC (memory transistors), dummy memory cells DMC2 to DMC0, and source-side select transistors STS and STSB. These configurations are connected in series between the bit line BL0 and the source line SL. Hereinafter, the drain-side select transistors STDT and STD, and the source-side select transistors STS and STSB are simply referred to as select transistors (STDT, STD, STS, and STSB) or the like in some cases.
The memory cell MC is a field-effect type transistor. The memory cell MC includes a semiconductor layer, a gate insulating film, and a gate electrode. The semiconductor layer functions as a channel region. The gate insulating film includes an electric charge accumulating film. The memory cell MC has a threshold voltage that changes according to an electric charge amount in the electric charge accumulating film. The memory cell MC stores 1 bit or a plurality of bits of data. Word lines WL are connected to respective gate electrodes of the plurality of memory cells MC corresponding to one memory string MS. These respective word lines WL are connected to all of the memory strings MS in one memory block BLK in common.
The dummy memory cells DMC0 to DMC5 are field-effect type transistors. The dummy memory cells DMC0 to DMC5 are basically configured similarly to the memory cell MC. However, the dummy memory cells DMC0 to DMC5 are not used to store data. Dummy word lines DWL0 to DWL5 are connected to gate electrodes of the dummy memory cells DMC0 to DMC5 corresponding to one memory string MS, respectively. These respective dummy word lines DWL0 to DWL5 are connected to all of the memory strings MS in one memory block BLK in common.
The select transistor (STDT, STD, STS, or STSB) is a field-effect type transistor. The select transistor (STDT, STD, STS, or STSB) includes a semiconductor layer, a gate insulating film, and a gate electrode. The semiconductor layer functions as a channel region. Select gate lines SGDT0, SGD0 to SGD4, SGS0, and SGSB0 are connected to gate electrodes of the select transistors (STDT, STD, STS, and STSB), respectively. One drain-side select gate line SGDT0 is connected to all of the memory strings MS in the circuit blk0 in common. The drain-side select gate lines SGD0 to SGD4 are connected to all of the memory strings MS in common in the string units SU0 to SU4, respectively. One source-side select gate line SGS0 is connected to all of the memory strings MS in the circuit blk0 in common. One source-side select gate line SGSB0 is connected to all of the memory strings MS in the circuit blk0 in common.
For example, as illustrated in
The memory string MS in the circuit blk1 is basically configured similarly to the memory string MS in the circuit blk0. However, select gate lines SGDT1, SGD5 to SGD9, SGS1, and SGSB1 are connected to gate electrodes of the select transistors (STDT, STD, STS, and STSB) in the circuit blk1, respectively. One drain-side select gate line SGDT1 is connected to all of the memory strings MS in the circuit blk1 in common. The drain-side select gate lines SGD5 to SGD9 are connected to all of the memory strings MS in common in the string units SU5 to SU9, respectively. One source-side select gate line SGS1 is connected to all of the memory strings MS in the circuit blk1 in common. One source-side select gate line SGSB1 is connected to all of the memory strings MS in the circuit blk1 in common.
Note that as illustrated as an example in
The voltage generation circuit VG (
The row decoder RD includes a plurality of circuits blkd (
Note that the wirings CG include two wirings CGSGDT corresponding to the drain-side select gate lines SGDT0 and SGDT1, ten wirings CGSGD corresponding to the drain-side select gate lines SGD0 to SGD9, a plurality of wirings CGWL corresponding to the plurality of word lines WL, six wirings CGDWL corresponding to the plurality of dummy word lines DWL0 to DWL5, two wirings CGSGS corresponding to the source-side select gate lines SGS0 and SGS1, and two wirings CGSGSB corresponding to the source-side select gate lines SGSB0 and SGSB1.
In the read operation, the write operation, and the like, for example, one signal supply line BLKSEL corresponding to a row address RA in the address register ADR (
The sense amplifier module SAM (
The cache memory CM (
To the cache memory CM, a decode circuit and a switch circuit (not illustrated) are connected. The decode circuit decodes a column address CA latched in the address register ADR (
The sequencer SQC (
The sequencer SQC generates a ready/busy signal and outputs the ready/busy signal to a terminal RY//BY. In a period where the terminal RY//BY is in an “L” state (a busy period), access to the memory die MD is basically inhibited. In a period where the terminal RY//BY is in an “H” state (a ready period), the access to the memory die MD is permitted. The terminal RY//BY is achieved by, for example, the pad electrode P described with reference to
The input/output control circuit I/O includes data signal input/output terminals DQ0 to DQ7, toggle signal input/output terminals DQS and /DQS, a plurality of input circuits, a plurality of output circuits, a shift register, and a buffer circuit. The plurality of input circuits, the plurality of output circuits, the shift register, and the buffer circuit are each connected to a terminal to which a power supply voltage VCCQ or the ground voltage Vss is applied.
The data signal input/output terminals DQ0 to DQ7, the toggle signal input/output terminals DQS and /DQS, and the terminal to which the power supply voltage VCCQ is applied are achieved by, for example, the pad electrodes P described with reference to
The plurality of input circuits include, for example, comparators connected to any of the data signal input/output terminals DQ0 to DQ7 or both of the toggle signal input/output terminals DQS and /DQS. The plurality of output circuits include, for example, Off Chip Driver (OCD) circuits connected to any of the data signal input/output terminals DQ0 to DQ7 or any of the toggle signal input/output terminals DQS and /DQS.
Circuit Configuration of Logic Circuit CTRThe logic circuit CTR (
For example, as illustrated in
For example, as illustrated in
For example, the semiconductor substrate 100 is made of P-type silicon (Si) containing P-type impurities, such as boron (B). On a surface of the semiconductor substrate 100, an N-type well region containing N-type impurities, such as phosphorus (P), a P-type well region containing P-type impurities, such as boron (B), a semiconductor substrate region in which the N-type well region or the P-type well region is not disposed, and an insulating region 100I of silicon oxide (SiO2) or the like are disposed.
Structure of Transistor Layer LTRFor example, as illustrated in
The respective N-type well region, P-type well region, and semiconductor substrate region of the semiconductor substrate 100 function as channel regions of the plurality of transistors Tr, one of electrodes of a plurality of capacitors, and the like constituting the peripheral circuit PC.
The respective plurality of electrodes gc included in the wiring layer GC function as the gate electrodes of the plurality of transistors Tr, the other electrodes of the plurality of capacitors, and the like constituting the peripheral circuit PC.
The contact CS extends in the Z-direction and is connected to the semiconductor substrate 100 or an upper surface of the electrode gc at a lower end. In a connection part between the contact CS and the semiconductor substrate 100, an impurity region containing N-type impurities or P-type impurities is disposed. For example, the contact CS may include a stacked film of a barrier conductive film, such as titanium nitride (TiN), and a metal film, such as tungsten (W), or the like.
Structures of Wiring Layers D0, D1, and D2For example, as illustrated in
The wiring layers D0, D1, and D2 include a plurality of wirings d0, d1, and d2, respectively. For example, the plurality of wirings d0, d1, and d2 may include a stacked film of a barrier conductive film, such as titanium nitride (TiN) and tantalum nitride (TaN), and a metal film, such as tungsten (W), copper (Cu), and aluminum (Al), or the like.
Structure of Memory Cell Array layer LMCA in Memory Hole region RMHFor example, as illustrated in
For example, as illustrated in
For example, as illustrated in
The conductive layer 110 is a substantially plate-shaped conductive layer extending in the X-direction. The conductive layers 110 include a plurality of through-holes provided corresponding to the semiconductor columns 120. Respective inner circumferential surfaces of the plurality of through-holes are opposed to outer circumferential surfaces of the semiconductor columns 120 via the gate insulating films 130. The conductive layer 110 may include a stacked film of a barrier conductive film, such as titanium nitride (TiN), and a metal film, such as tungsten (W), or the like. For example, the conductive layer 110 may contain polycrystalline silicon containing impurities, such as phosphorus (P) or boron (B), or the like. Between the respective adjacent plurality of conductive layers 110 arranged in the Z-direction, insulating layers 101, such as silicon oxide (SiO2), are disposed.
As illustrated in
The conductive layer 112 functions as the source line SL (
Among the plurality of conductive layers 110, one or a plurality of conductive layers 110 positioned as the lowermost layers function as the source-side select gate lines SGSB0 and SGSB1 and the gate electrodes of the plurality of source-side select transistors STSB connected to them. These plurality of conductive layers 110 are electrically independent in every memory block BLK. Note that in the example of
One or a plurality of conductive layers 110 positioned above them function as the source-side select gate lines SGSO and SGS1 (
Three conductive layers 110 positioned above them function as gate electrodes of the dummy word lines DWL0 to DWL2 and the dummy memory cells DMC0 to DMC2 connected to them. These plurality of conductive layers 110 are electrically independent in every memory block BLK. Note that in the example of
A plurality of conductive layers 110 positioned above them function as the word lines WL (
Three conductive layers 110 positioned above them function as the dummy word lines DWL3 to DWL5 and the gate electrodes of the dummy memory cells DMC3 to DMC5 connected to them. These plurality of conductive layers 110 are electrically independent in every memory block BLK. Note that in the example of
One or a plurality of conductive layers 110 positioned above them functions as the drain-side select gate lines SGD0 to SGD9 and the gate electrodes of the plurality of drain-side select transistor STD (
One or a plurality of conductive layers 110 positioned above them function as the drain-side select gate lines SGDT0 and SGDT1 and the gate electrodes of the plurality of drain-side select transistors STDT (
For example, as illustrated in
An impurity region containing N-type impurities, such as phosphorus (P), is disposed in an upper end portion of the semiconductor column 120. This impurity region is connected to the bit line BL0 or the bit line BL1 via a contact Ch and a contact Vy (
An impurity region containing N-type impurities, such as phosphorus (P), is disposed in a lower end portion of the semiconductor column 120. This impurity region is connected to the conductive layer 112 (
The gate insulating film 130 (
Note that
As illustrated in
As illustrated in
As illustrated in
In the contact connection sub-region rCC1, end portions in the X-direction of the plurality of conductive layers 110 that function as the drain-side select gate lines SGDT0 and SGD0 to SGD4, or end portions in the X-direction of the plurality of conductive layers 110 that function as the drain-side select gate lines SGDT1 and SGD5 to SGD9 are disposed. In the contact connection sub-region rcc1, a plurality of contacts CC arranged in a matrix viewed in the Z-direction are disposed. For example, as illustrated in
Among the plurality of contacts CC arranged in the X-direction, the contact CC closest to the memory hole region RMH is connected to the first conductive layer 110 counted from the upper side. The contact CC second closest to the memory hole region RMH is connected to the second conductive layer 110 counted from the upper side. Hereinafter, similarly, the contact CC a-th (a is a positive integer of 1 or more) closest to the memory hole region RMH is connected to the a-th conductive layer 110 counted from the upper side. These plurality of contacts CC are connected to the drain electrodes of the transistors Tr via wirings M0 in the wiring layer M0, the wirings d0, d1, and d2 in the wiring layers D0, D1, and D2, and the contacts CS.
For example, as illustrated in
As illustrated in
As illustrated in
As illustrated in
Note that as illustrated in
The conductive layers 110 that function as the source-side select gate lines SGS0 and SGS1 are also separated in the X-direction in the second hook-up region RHU2. These conductive layers 110 are connected to the respective contacts CC (see
As illustrated in
Although the illustration is omitted, the conductive layers 110 that function as the dummy word lines DWL0 to DWL5 are also not separated in the X-direction in the second hook-up region RHU2. These conductive layers 110 are connected to one contact CC.
The plurality of contacts CC disposed in the contact connection sub-region rCC2 are connected to the drain electrodes of the transistors Tr via the wirings m0 in the wiring layer M0, the wirings d0, d1, and d2 in the wiring layers D0, D1, and D2, and the contacts CS.
As illustrated in
The insulating layers STo (
The insulating layer 110A is an approximately plate-shaped insulating layer extending in the X-direction. The insulating layer 110A may include an insulating layer, such as silicon nitride (Si3N4). Between the respective adjacent plurality of insulating layers 110A arranged in the Z-direction, insulating layers, such as silicon oxide (SiO2), are disposed.
The plurality of contacts C4 are arranged in the X-direction. The contact C4 may include a stacked film of a barrier conductive film, such as titanium nitride (TiN), and a metal film, such as tungsten (W), or the like. For example, as illustrated in
As illustrated in
Next, with reference to
Note that
In the following description, an example of performing the read operation on the plurality of memory cells MC in the string unit SU0 will be described.
In the following description, a word line WL target for the operation is referred to as a selected word line WL and the WL other than the selected word line WL are referred to as unselected WL in some cases. In the following description, among the plurality of memory cells MC included in a string unit SU0 target for the operation, the memory cell MC connected to the selected word line WL is referred to as a selected memory cell MC in some cases.
Moreover, in the following description, an execution unit of the read operation or the write operation is referred to as a page in some cases. The range of the page is appropriately adjustable.
Note that, in the following description, an example in which the memory cell MC stores N-bit data, each of the string units SU0 to SU9 includes the number of pages N times of the number of WL included in the memory block BLK will be shown. Additionally, an example in which these plurality of pages each store the data having the same number of bits as the number of memory strings MS included in one of the string units SU0 to SU9 will be shown.
In the following description, a page target for the operation will be referred to as a selected page PG in some cases. The selected page PG is one of the plurality of pages included in the string unit SU0 target for the operation. Gate electrodes of the plurality of memory cells MC corresponding to the selected page PG are connected to the selected WL.
In the read operation, for example, a voltage VDD is applied to the plurality of bit lines BL0 and the plurality of bit lines BL1. Accordingly, the voltage VDD is transferred to the drain-side select transistor STDT.
In the read operation, for example, a voltage VSG is applied to the drain-side select gate lines SGDTO and SGD0. The voltage VSG is larger than the voltage VDD. A voltage difference between the voltage VSG and the voltage VDD is larger than a threshold voltage when the drain-side select transistors STDT and STD are caused to function as NMOS transistors. Therefore, electron channels are formed in channel regions of the drain-side select transistors STDT and STD. Accordingly, the voltage VDD is transferred to the dummy memory cell DMC5 in the string unit SU0.
In the read operation, for example, the ground voltage VSS is applied to the drain-side select gate lines SGDT1 and SGD1 to SGD9. The ground voltage VSS is smaller than the voltage VDD. A voltage difference between the voltage VDD and the voltage VSS is smaller than the threshold voltage when the drain-side select transistors STDT and STD are caused to function as NMOS transistors. Therefore, a channel is not formed in the channel region of the drain-side select transistor STDT or STD. Therefore, the voltage VDD is not transferred to the dummy memory cells DMC5 in the string units SU1 to SU9.
In the read operation, for example, a voltage VDWLR3 to a voltage VDWLR5 are applied to the dummy word lines DWL3 to DWL5. The voltage VDWLR3 is larger than a voltage VDWLR4. The voltage VDWLR4 is larger than the voltage VDWLR5.The voltage VDWLR5 is, for example, larger than the voltage VSG. Voltage differences between the voltage VDWLR3 to the voltage VDWLR5 and the voltage VDD are larger than a threshold voltage when the dummy memory cells DMC3 to DMC5 are caused to function as NMOS transistors. Therefore, electron channels are formed in channel regions in the dummy memory cells DMC3 to DMC5. Accordingly, the voltage VDD is transferred to the memory cells MC in the string unit SU0.
In the read operation, for example, a voltage VSRC is applied to the source line SL. The voltage VSRC is larger than the ground voltage VSS and smaller than the voltage VDD. The voltage VSRC may have a magnitude same extent to the ground voltage VSS. Accordingly, the voltage VSRC is transferred to the source-side select transistor STSB.
In the read operation, for example, the voltage VSG is applied to the source-side select gate lines SGSB0 and SGSO. Thus, electron channels are formed in channel regions in the source-side select transistors STSB and STS. Thus, the voltage VSRC is transferred to the dummy memory cells DMC0 in the string units SU0 to SU4.
In the read operation, for example, the ground voltage VSS is applied to the source-side select gate lines SGSB1 and SGS1. Therefore, the channel is not formed in the channel region in the source-side select transistor STSB or STS. Therefore, the voltage VSRC is not transferred to the dummy memory cells DMC0 in the string units SU5 to SU9.
In the read operation, for example, a voltage VDWLR0 to a voltage VDWLR2 are applied to the dummy word lines DWL0 to DWL2. The voltage VDWLR2 is larger than a voltage VDWLR1. The voltage VDWLR1 is larger than the voltage VDWLR0. The voltage VDWLR0 is, for example, larger than the voltage VSG. Additionally, voltage differences between the voltage VDWLR0 to the voltage VDWLR2 and the voltage VSRC are larger than a threshold voltage when the dummy memory cells DMC0 to DMC2 are caused to function as NMOS transistors. Accordingly, electron channels are formed in the channel regions in the dummy memory cells DMC0 to DMC2. Thus, the voltage VSRC is transferred to the memory cells MC in the string units SU0 to SU4.
In the read operation, for example, a read pass voltage VREAD is applied to the unselected WL. The read pass voltage VREAD is larger than the voltages VDWLR2 and VDWLR3. Voltage differences between the read pass voltage VREAD and the voltages VDD and VSRC are larger than a threshold voltage when the unselected memory cells MC are caused to function as an NMOS transistor regardless of the data stored in the unselected memory cells MC. Therefore, electron channels are formed in channel regions in the unselected memory cells MC.
In the read operation, for example, a read voltage VCGR is applied to the selected word line WL. The read voltage VCGR is smaller than the read pass voltage VREAD.
Here, when the selected memory cell stores specific data, a voltage difference between the read voltage VCGR and the voltage VSRC is larger than the threshold voltage when the selected memory cell MC is caused to function as an NMOS transistor. Accordingly, in such a case, an electron channel is formed in a channel region in the selected memory cell MC, and the bit line BL0 is electrically conductive to the source line SL. Thus, a current flows through the bit line BL0.
On the other hand, when the selected memory cell does not store the specific data, a voltage difference between the read voltage VCGR and the voltage VSRC is smaller than the threshold voltage when the selected memory cell MC is caused to function as an NMOS transistor. Therefore, in such a case, an electron channel is not formed in the channel region in the selected memory cell MC, and the bit line BL0 is not electrically conductive to the source line SL. Therefore, the current does not flow through the bit line BL0.
Therefore, in the read operation, the sense amplifier module SAM (
Next, with reference to
Note that
In the following description, an example of performing the read operation on the plurality of memory cells MC in the string unit SU0 will be described.
In the write operation, for example, the voltage VSRC is applied to the bit line BL0 connected to the selected memory cell MC subject to adjustment of the threshold voltage among the plurality of selected memory cells MC. Thus, the voltage VSRC is transferred to the drain-side select transistor STDT connected to this bit line BL0. Hereinafter, the memory cell MC subject to adjustment of the threshold voltage among the plurality of selected memory cells MC is referred to as a “write memory cell MC” in some cases.
In the write operation, for example, the voltage VDD is applied to the bit line BL0 connected to the selected memory cell MC not subject to adjustment of the threshold voltage among the plurality of selected memory cells MC. Thus, the voltage VDD is transferred to the drain-side select transistor STDT connected to this bit line BL0. Hereinafter, the selected memory cell MC not subject to adjustment of the threshold voltage among the plurality of selected memory cells MC is referred to as an “inhibited memory cell MC” in some cases.
In the write operation, for example, the voltage VSRC is applied to the plurality of bit lines BL1. Thus, the voltage VSRC is transferred to the drain-side select transistor STDT connected to the bit line BL1.
In the write operation, for example, a voltage VSGDW is applied to the drain-side select gate lines SGDT0 and SGD0. The voltage VSCDW is larger than the voltages VSRC and VDD.
Here, a voltage difference between the voltage VSGDW and the voltage VSRC is larger than the threshold voltage when the drain-side select transistors STDT and STD are caused to function as NMOS transistors. Therefore, electron channels are formed in the channel regions in the drain-side select transistors STDT and STD electrically connected to the write memory cell MC. Thus, the voltage VSRC is transferred to the dummy memory cell DMC5 electrically connected to the write memory cell MC.
On the other hand, a voltage difference between the voltage VSGDW and the voltage VDD is smaller than the threshold voltage when the drain-side select transistors STDT and STD are caused to function as NMOS transistors. Accordingly, an electron channel is not formed in the channel region in the drain-side select transistor STDT or STD electrically connected to the inhibited memory cell MC. Accordingly, the voltage VSRC is not transferred to the dummy memory cell DMC5 electrically connected to the inhibited memory cells MC.
In the write operation, for example, the ground voltage VSS is applied to the drain-side select gate lines SGDT1 and SGD1 to SGD9. Accordingly, a channel is not formed in the channel region in the drain-side select transistor STDT or STD. Therefore, the voltage VSRC is not transferred to the dummy memory cells DMC5 in the string units SU1 to SU9.
In the write operation, for example, a voltage VDWLW3 to a voltage VDWLW5 are applied to the dummy word lines DWL3 to DWL5. The voltage VDWLW3 is larger than the voltage VDWLW4. The voltage VDWLW4 is larger than the voltage VDWLW5. The voltage VDWLW5 is, for example, larger than the voltage VSG. Voltage differences between the voltage VDWLW3 to the voltage VDWLW5 and the voltage VSRC are larger than the threshold voltage when the dummy memory cells DMC3 to DMC5 are caused to function as NMOS transistors. Therefore, electron channels are formed in the channel regions in the dummy memory cells DMC3 to DMC5. Thus, the voltage VSRC is transferred to the memory cell MC electrically connected to the write memory cell MC.
In the write operation, for example, the voltage VSRC is applied to the source line SL. Thus, the voltage VSRC is transferred to the source-side select transistor STSB.
In the write operation, for example, the ground voltage VSS is applied to the source-side select gate lines SGSB0, SGS0, SGSB1, and SGS1. Therefore, a channel is not formed in the channel region in the source-side select transistor STSB or STS. Accordingly, the voltage VSRC is not transferred to the dummy memory cells DMC0 in the string units SU0 to SU9.
In the write operation, for example, a voltage VDWLW0 to a voltage VDWLW2 are applied to the dummy word lines DWL0 to DWL2. The voltage VDWLW2 is larger than the voltage VDWLW1. The voltage VDWLW1 is larger than the voltage VDWLW0.
In the write operation, for example, a write pass voltage VPASS is applied to the unselected WL. The write pass voltage VPASS is larger than the voltages VDWLW2 and VDWLW3. A voltage difference between the write pass voltage VPASS and the voltage VSRC is larger than the threshold voltage when the unselected memory cells MC are caused to function as NMOS transistors, regardless of the data stored in the unselected memory cells MC. Accordingly, electron channels are formed in the channel regions in the unselected memory cells MC.
In the write operation, for example, a program voltage VPGM is applied to the selected word line WL. The program voltage VPGM is larger than the write pass voltage VPASS.
Here, the voltage VSRC is applied to a channel in the write memory cell MC. A comparatively large electric field is generated between the channel and the selected word line WL. Thus, electrons in a channel in the semiconductor column 120 tunnel in the electric charge accumulating film 132 (
A channel in the inhibited memory cell MC is in electrically floating state, and a voltage of this channel increases up to around the write pass voltage VPASS by capacitive coupling with the unselected word line WL. Between the channel and the selected word line WL, the large electric field as described above does not occur. Therefore, the electrons in the channel of the semiconductor column 120 do not tunnel in the electric charge accumulating film 132 (
Note that channels in the memory cells MC in the string units SU1 to SU9 are also in the electrically floating states. Therefore, electrons in the channels in the memory cells MC in the string units SU1 to SU9 do not tunnel in the electric charge accumulating films 132 (
Next, with reference to
Note that
In the following description, an example of performing the erase operation on the plurality of memory cells MC in the string units SU0 to SU4 will be described.
In the erase operation, for example, an erase voltage VERA is applied to the plurality of bit lines BL0 and the plurality of bit lines BL1. Thus, the erase voltage VERA is transferred to the drain-side select transistor STDT. The erase voltage VERA is larger than the write pass voltage VPASS. The erase voltage VERA may have a magnitude to the same extent of the program voltage VPGM or may be larger or smaller than the program voltage VPGM.
In the erase operation, for example, a voltage VSGDT is applied to the drain-side select gate line SGDT0. The voltage VSGDT is smaller than the erase voltage VERA. Thus, in the channel region in the drain-side select transistor STDT corresponding to the drain-side select gate line SGDT0, a Gate Induced Drain Leakage (GIDL) occurs to generate an electron and hole pair. The electrons move to the bit line BL0 side and the holes move to the memory cells MC side.
In the erase operation, for example, a voltage VSGD0 is applied to the drain-side select gate lines SGD0 to SGD4. The voltage VSCD0 is smaller than the erase voltage VERA. The voltage VSCD0 may be equal to the voltage VSGDT or may be larger than the voltage VSGDT. A voltage difference between the erase voltage VERA and the voltage VSCD0 is larger than an absolute value of a threshold voltage when the drain-side select transistor STD is caused to function as a PMOS transistor. Therefore, hole channels are formed in the channel region in the drain-side select transistor STD. Thus, the holes are supplied to the dummy memory cells DMC5 in the string units SU0 to SU4.
In the erase operation, for example, the erase voltage VERA is applied to the drain-side select gate line SGDT1. Accordingly, the GIDL does not occur in the channel region in the drain-side select transistor STDT corresponding to the drain-side select gate line SGDT1, and the electron and hole pair does not occur.
In the erase operation, for example, the erase voltage VERA is applied to the drain-side select gate lines SGD5 to SGD9.
In the erase operation, for example, a voltage VDWLE3 to a voltage VDWLE5 are applied to the dummy word lines DWL3 to DWL5. The voltage VDWLE3 is smaller than the voltage VDWLE4 . The voltage VDWLE4 is smaller than the voltage VDWLE5. The voltage VDWLE5 is, for example, smaller than the voltage VSGD0. Voltage differences between the voltage VDWLE3 to the voltage VDWLE5 and the erase voltage VERA are larger than an absolute value of a threshold voltage when the dummy memory cells DMC3 to DMC5 are caused to function as PMOS transistors. Accordingly, hole channels are formed in the channel regions in the dummy memory cells DMC3 to DMC5. Thus, the holes are transferred to the memory cells MC in the string units SU0 to SU4.
In the erase operation, for example, the erase voltage VERA is applied to the source line SL. Thus, the erase voltage VERA is transferred to the source-side select transistor STSB.
In the erase operation, for example, a voltage VSCSB is applied to the source-side select gate line SGSB0. The voltage VSCSB is smaller than the erase voltage VERA. Thus, a GIDL occurs in the channel region in the source-side select transistor STSB corresponding to the source-side select gate line SGSB0 to generate an electron and hole pair. The electrons move to the source line SL side and the holes move to the memory cells MC side.
In the erase operation, for example, a voltage VSGS0 is applied to the source-side select gate line SGS0. The voltage VSGS0 is smaller than the erase voltage VERA. The voltage VSGS0 may be equal to the voltage VSGSB or may be larger than the voltage VSGSB. A voltage difference between the erase voltage VERA and the voltage VSGS0 may be larger than an absolute value of a threshold voltage when the source-side select transistor STS is caused to function as a PMOS transistor. Therefore, hole channels are formed in the channel region in the source-side select transistor STS. Thus, the holes are supplied to the dummy memory cells DMC0 in the string units SU0 to SU4.
In the erase operation, for example, the erase voltage VERA is applied to the source-side select gate line SGSB1. Therefore, the GIDL does not occur in the channel region in the source-side select transistor STSB corresponding to the source-side select gate line SGSB1, and the electron and hole pair does not occur.
In the erase operation, for example, the erase voltage VERA is applied to the source-side select gate line SGS1.
In the erase operation, for example, a voltage VDWLE0 to a voltage VDWLE2 are applied to the dummy word lines DWL0 to DWL2. The voltage VDWLE2 is smaller than the voltage VDWLE1 . The voltage VDWLE1 is smaller than the voltage VDWLE0. The voltage VDWLE0 is, for example, smaller than the voltage VSGS0. Voltage difference between the voltage VDWLE0 to the voltage VDWLE2 and the erase voltage VERA are larger than an absolute value of a threshold voltage when the dummy memory cells DMC0 to DMC2 are caused to function as PMOS transistors. Accordingly, hole channels are formed in the channel regions in the dummy memory cells DMC0 to DMC2. Thus, the holes are transferred to the memory cells MC in the string unit SU0.
In the erase operation, for example, the ground voltage VSS is applied to the word line WL.
Here, holes are supplied to channel regions in the memory cells MC in the string units SU0 to SU4. A comparatively large electric field is generated between the channel and the word line WL. Thus, holes in the channel in the semiconductor column 120 tunnel in the electric charge accumulating film 132 (
On the other hand, holes are not supplied to channel regions in the memory cells MC in the string units SU5 to SU9. Between the channel and the word line WL, the large electric field as described above does not occur. Therefore, threshold voltages in the memory cells MC in the string units SU5 to SU9 do not decrease.
In the examples of
At timing T101 in the erase operation, the application of the voltage to the bit lines BL0 and BL1, the drain-side select gate lines SGDT1 and SGD5 to SGD9, the source line SL, and the source-side select gate lines SGSB1 and SGS1 is started. In the following description, the voltage applied to these wirings is referred to as a voltage VE0 in some cases.
At timing T102, the application of the voltage to the drain-side select gate lines SGDT0 and SGD0 to SGD4, and the source-side select gate lines SGSB0 and SGS0 is started. In the following description, the voltage applied to these wirings is referred to as a voltage VE1 in some cases. In the illustrated example, a voltage difference between the voltage VE0 and the voltage VE1 is maintained from timing T102 to at and after timing T105.
At timing T103, the application of the voltage to the dummy word lines DWL5, DWL4, DWL1, and DWL0 is started. In the following description, the voltage applied to these wirings is referred to as a voltage VE2 in some cases. In the illustrated example, voltage differences between the voltage VE0, the voltage VE1, and the voltage VE2 are maintained from timing T103 to at and after timing T105.
At timing T104, the application of the voltage to the dummy word lines DWL3 and DWL2 is started. In the following description, the voltage applied to these wirings is referred to as a voltage VE3 in some cases. In the illustrated example, voltage differences between the voltage VE0, the voltage VE1, the voltage VE2, and the voltage VE3 are maintained from timing T104 to at and after timing T105.
At timing T105, the voltage applied to each of the wirings reaches the magnitude described with reference to
As described with reference to
Here, in this semiconductor memory device, the page is the execution unit of the read operation and the write operation, and the memory block BLK is the execution unit of the erase operation in some cases. Here, for example, in a case where data that is not the erase target remains in the memory block BLK as the erase target, it is necessary to write this data to another memory block BLK, and erase the data in the memory block BLK after that. Hereinafter, this operation is referred to as a garbage collection in some cases.
Here, when the number of the memory cells MC included in the memory block BLK increases, the number of executions of the garbage collection increases in some cases. In this case, the number of executions of the write operation and the erase operation on the memory cells MC increases, and this leads to short service life of the memory cells MC in some cases.
To reduce the short service life of the memory cells MC, for example, it is considered that one memory block BLK is physically divided into the two memory blocks BLK. However, in this case, it is necessary to dispose the two second hook-up regions RHU2 corresponding to the divided two memory blocks BLK, and this possibly results in reduction in integration degree.
Therefore, the semiconductor memory device according to this embodiment is configured to be able to independently erase the data in the memory cells MC in the circuit blk0 and the memory cells MC in the circuit blk1. This configuration allows reducing the short service life of the memory cells MC in association with the increase in the number of executions of the garbage collection while reducing the decrease in integration degree.
Additionally, with the semiconductor memory device according to this embodiment, the different voltages can be applied to the select gate lines SGDT0, SGD0 to SGD4, SGS0, and SGSB0 corresponding to the circuit blk0 and the select gate lines SGDT1, SGD5 to SGD9, SGS1, and SGSB1 corresponding to the circuit blk1. With this configuration, in the erase operation, a GIDL can be generated in both of the drain-side select transistor STDT and the source-side select transistor STSB. Thus, stabilization of the erase operation is possible.
Designation Method of Erase OperationThe erase operation described with reference to
Next, with reference to
In this case, the erase operation corresponding to
Next, with reference to
Note that as described with reference to
At timing t101, the controller die CD (
At timing t102, the controller die CD inputs the data A301 to the memory die MD as address data DADD. That is, in a state where the voltages of the data signal input/output terminals DQ0 to DQ7 are set to “H” or “L” according to the respective bits of the data A301, “L” is input to the external control terminal CLE, and “H” is input to the external control terminal ALE, the external control terminal /WE is risen from “L” to “H”. The data A301 is a part of the row address RA. The data A301 includes, for example, a block address to identify the memory block BLK (
At timing t103, the controller die CD inputs the data A302 to the memory die MD as the address data DADD. The data A302 is a part of the row address RA. The data A302 includes, for example, the block address and a page address.
At timing t104, the controller die CD inputs the data A303 to the memory die MD as the address data DADD. The data A303 includes a chip address. The chip address is data to identify one memory die MD from the plurality of memory dies MD controlled by the controller die CD.
At timing t105, the controller die CD inputs the data D0h to the memory die MD as the command data DCMD. The data D0h is a command indicative of the end of the input of the command set regarding the erase operation.
At timing t106, the terminal RY//BY enters the “L” state from the “H” state, and access to the memory die MD is inhibited. The erase operation is performed in the memory die MD.
At timing t107, the erase operation in the memory die MD ends. The terminal RY//BY enters the “H” state from the “L” state, and the access to the memory die MD is permitted.
At timing t108, the controller die CD inputs, for example, data 70h to the memory die MD as the command data DCMD. The data 70h is a command that requests an output of status data DST latched in the status register STR (
At timing t109, the controller die CD causes the memory die MD to output, for example, the data D301. That is, in a state where “L” is input to the external control terminal CLE and “L” is input to the external control terminal ALE, the external control terminal /RE falls from “H” to “L” and the external control terminal RE is risen from “L” to “H”. In association with this, the voltages of the data signal input/output terminals DQ0 to DQ7 are set to “H” or “L” according to the respective bits of the data D301. The controller die CD obtains the data D301 by the amount of eight bits. The data D301 is the status data DST .
Next, with reference to
The erase operation corresponding to
Note that the 8-bit data constituting the data XXh each may be “0” or may be “1”. Among the 8-bit data constituting the data XXh, the data from the first bit to the fourth bit may be the same or may be different from the data from the fifth bit to the eighth bit.
Second EmbodimentNext, with reference to
The semiconductor memory device according to the second embodiment is basically configured similarly to the semiconductor memory device according to the first embodiment.
However, as illustrated in
As illustrated in
Note that
With the semiconductor memory device according to the second embodiment, when the erase operation is performed, the command set CSE0 as described with reference to
Next, a semiconductor memory device according to the third embodiment will be described with reference to
The semiconductor memory device according to the third embodiment is basically configured similarly to the semiconductor memory device according to the first embodiment. However, as illustrated in
As illustrated in
The other conductive layer 312 is disposed across the whole memory hole region RMH at the other side in the X-direction (for example, the positive side in the X-direction in
The semiconductor memory device according to the third embodiment is configured to be able to apply different voltages to these two conductive layers 312.
Next, with reference to
Note that
The erase operation of the semiconductor memory device according to the third embodiment is basically performed similarly to the erase operation of the semiconductor memory device according to the first embodiment.
However, in the erase operation of the semiconductor memory device according to the third embodiment, for example, as illustrated in
In this erase operation, for example, the ground voltage VSS is applied to the drain-side select gate line SGDT1. Therefore, a GIDL does not occur in the channel region in the drain-side select transistor STDT corresponding to the drain-side select gate line SGDT1, and an electron and hole pair does not occur.
In this erase operation, for example, the ground voltage VSS is applied to the drain-side select gate lines SGD5 to SGD9.
In this erase operation, for example, the erase voltage VERA is applied to the source line SL0. Thus, the erase voltage VERA is transferred to the source-side select transistor STSB connected to the source line SL0.
In this erase operation, for example, the voltage VSRC is applied to the source line SL1. Thus, the voltage VSRC is transferred to the source-side select transistor STSB connected to the source line SL1.
In this erase operation, for example, the ground voltage VSS is applied to the source-side select gate line SGSB1. Therefore, the GIDL does not occur in the channel region in the source-side select transistor STSB corresponding to the source-side select gate line SGSB1, and the electron and hole pair does not occur.
In this erase operation, for example, the ground voltage VSS is applied to the source-side select gate line SGS1.
The erase operation illustrated as an example in
In the erase operation described with reference to
Therefore, the semiconductor memory device according to the third embodiment is configured to be able to apply different voltages to the source line SL0 corresponding to the circuit blk0 and the source line SL1 corresponding to the circuit blk1. Additionally, in the erase operation targeting the memory cells MC in the circuit blk0, not the erase voltage VERA but the voltage VSRC is applied to the bit line BL1 and the source line SL1. Further, the ground voltage VSS is applied to the drain-side select gate lines SGDT1 and SGD5 to SGD9 and the source-side select gate lines SGSB1 and SGS1.
This method allows reducing the voltage differences between the drain-side select gate lines SGD5 to SGD9 and the dummy word line DWL5. Additionally, the voltage difference between the source-side select gate line SGS1 and the dummy word line DWL0 can be reduced, thus allowing reducing the leakage current as described above.
Fourth EmbodimentNext, with reference to
The semiconductor memory device according to the fourth embodiment is basically configured similarly to the semiconductor memory device according to the first embodiment. However, as illustrated in
Each of the circuits blk0a, blk0b, blkla, and blklb includes five string units. Each of these five string units includes the plurality of memory strings MS.
In the example of
In the example of
In the example of
In the example of
Next, with reference to
The semiconductor memory device according to the fourth embodiment is basically configured similarly to the semiconductor memory device according to the first embodiment. However, as illustrated in
The memory die MD4 is basically configured similarly to the memory die MD. For example, as described with reference to
On the other hand, for example, as illustrated in
Note that as illustrated in
As illustrated in
As illustrated in
As illustrated in
As illustrated in
As illustrated in
As illustrated in
Although the illustration is omitted, the conductive layers 110 that function as the source-side select gate lines SGS1a, SGSB1a, SGS1b, and SGSB1b between the third memory hole region RMH and the fourth memory hole region RMH counted from one side in the X-direction are separated in the X-direction. That is, the conductive layers 110 that function as the source-side select gate lines SGS1a and SGSB1a and the conductive layers 110 that function as the source-side select gate lines SGS1b and SGSB1b are arranged in the X-direction and spaced in the X-direction. For example, as illustrated as an example in
Note that in the examples of
The semiconductor memory device according to the fourth embodiment is configured to be able to independently erase the data in the memory cells MC in the circuit blk0a, the memory cells MC in the circuit blk0b, the memory cells MC in the circuit blkla, and the memory cells MC in the circuit blklb.
EffectsThe semiconductor memory device according to this embodiment allows further preferably reducing the short service life of the memory cells MC in association with the increase in the number of executions of the garbage collection while reducing the decrease in integration degree.
Fifth EmbodimentNext, with reference to
The semiconductor memory device according to the fifth embodiment is basically configured similarly to the semiconductor memory device according to the fourth embodiment. However, as illustrated in
The first conductive layer 512 counted from one side in the X-direction (for example, the negative side in the X-direction in
The second conductive layer 512 counted from one side in the X-direction is disposed across the whole second memory hole region RMH counted from one side in the X-direction and the whole first hook-up region RHU1 and a part of the second hook-up region RHU2 corresponding to this. This conductive layer 512 functions as a source line SLOb corresponding to the circuit blk0b (
The third conductive layer 512 counted from one side in the X-direction is disposed across the whole third memory hole region RMH counted from one side in the X-direction and the whole first hook-up region RHU1 and a part of the second hook-up region RHU2 corresponding to this. This conductive layer 512 functions as a source line SL1a corresponding to the circuit blkla (
The fourth conductive layer 512 counted from one side in the X-direction is disposed across the whole fourth memory hole region RMH counted from one side in the X-direction and the whole third hook-up region RHU3 corresponding to this. This conductive layer 512 functions as a source line SLlb corresponding to the circuit blklb (
The semiconductor memory device according to the fifth embodiment can apply different voltages to these four conductive layers 512.
The semiconductor memory device according to the fifth embodiment is configured to be able to independently erase the data in the memory cells MC in the circuit blk0a, the memory cells MC in the circuit blk0b, the memory cells MC in the circuit blkla, and the memory cells MC in the circuit blklb.
EffectsThe semiconductor memory device according to the fifth embodiment allows reducing the voltage difference between the drain-side select gate line corresponding to the memory cells MC that are not the targets for erase operation and the dummy word line DWL5 at the erase operation. Additionally, the voltage difference between the source-side select gate line corresponding to the memory cells MC that are not the targets for erase operation and the dummy word line DWL0 can be reduced, thus allowing reducing the leakage current as described above.
Other EmbodimentsThe semiconductor memory devices according to the first embodiment to the fifth embodiment have been described above. However, the semiconductor memory devices according to these embodiments are only examples and specific configurations, operations, and the like are adjustable as appropriate.
For example, the semiconductor memory device according to the first embodiment is configured to be able to perform the erase operation corresponding to
For example, as described with reference to
For example, in the semiconductor memory device according to the first embodiment, the common string address may be allocated to the string unit SU0 and the string unit SU5 or the different string addresses may be allocated. Similarly, the common string address may be allocated to each of the string units SU1 and SU6, the string units SU2 and SU7, the string units SU3 and SU8, and the string units SU4 and SU9, or the different string addresses may be allocated.
When the common string address is allocated to each of the string units SU0 and SU5, the string units SU1 and SU6, the string units SU2 and SU7, the string units SU3 and SU8, and the string units SU4 and SU9, the page as the execution unit of the read operation and the write operation may be shared by the combination of these string units SU. For example, when the memory cell MC stores N-bit (N is an integer of one or more) data, the string units SU0 and SU5 may include the number of pages N times of the number of WL included in the memory block BLK. In this case, these plurality of pages may each store the data having the same number of bits as the number of the memory strings MS included in the string units SU0 and SU5. Similarly, each of the string units SU1 and SU6, the string units SU2 and SU7, the string units SU3 and SU8, and the string units SU4 and SU9 may include the number of pages N times of the number of WL included in the memory block BLK. In this case, these plurality of pages may each store the data having the same number of bits as the number of the memory strings MS included in the two string units SU.
In this case, for example, by inputting the predetermined command set to the memory die MD, the read operation and the write operation in which any one of the string units SU0 and SU5, the string units SU1 and SU6, the string units SU2 and SU7, the string units SU3 and SU8, and the string units SU4 and SU9 and the page corresponding to one selected word line WL are the execution unit of the operations may be performed. Moreover, by adding the data XXh as described with reference to
When different string addresses are allocated to the respective string unit SU0 and SU5, string units SU1 and SU6, string units SU2 and SU7, string units SU3 and SU8, and string units SU4 and SU9, for example, by inputting the predetermined command set to the memory die MD, the read operation and the write operation as described with reference to
Additionally, the erase operation corresponding to
The voltages as shown in
For example, the voltages applied to the bit line BL, the drain-side select gate lines SGD5 to SGD9 and SGDT1, the source line SL, and the source-side select gate lines SGS1 and SGSB1 may be voltages of different magnitudes. Similarly, the voltages applied to the dummy word lines DWL5 and DWL0 may have different magnitudes. Similarly, the voltages applied to the drain-side select gate line SGDT0, the dummy word lines DWL4 and DWL1, and the source-side select gate line SGSB0 may have different magnitudes. Similarly, the voltages applied to the dummy word lines DWL3 and DWL2 may have different magnitudes.
For example, an initial voltage (the voltage at timing T101 in
Moreover, the voltages shown in
At least one of the drain-side select transistor STDT and the source-side select transistor STSB can be omitted. In this case, at least one of the functions of the drain-side select transistor STDT and the source-side select transistor STSB may be achieved by at least one of the drain-side select transistor STD and the source-side select transistor STS.
For example, the example of
In the example of
At timing T101 in the erase operation, the application of the voltage to the source line SL and the source-side select gate line SGS1 is started.
At timing T202, the application of the voltage to the source-side select gate line SGS0 is started. In the illustrated example, voltage differences between the source line SL and the source-side select gate lines SGS0 and SGS1 are maintained from timing T202 to at and after timing T105.
At timing T203, the application of the voltage to the dummy word line DWL0 is started. In the illustrated example, from timing T203 to at and after timing T105, voltage differences between the source line SL, the source-side select gate lines SGS0 and SGS1, and the dummy word line DWL0 are maintained.
At timing T204, the application of the voltage to the dummy word line DWL1 is started. In the illustrated example, from timing T204 to at and after timing T105, voltage differences between the source line SL, the source-side select gate lines SGS0 and SGS1, and the dummy word lines DWL0 and DWL1 are maintained.
At timing T205, the application of the voltage to the dummy word line DWL2 is started. In the illustrated example, from timing T205 to timing T105, voltage difference between the source line SL, the source-side select gate lines SGS0 and SGSland the dummy word lines DWL0, DWL1, and DWL2 is maintained.
In the semiconductor memory device according to the third embodiment as well, the common string address may be allocated to each of the string units SU0 and SU5, the string units SU1 and SU6, the string units SU2 and SU7, the string units SU3 and SU8, and the string units SU4 and SU9, or the different string addresses may be allocated.
In the semiconductor memory device according to the third embodiment as well, similarly to the semiconductor memory device according to the second embodiment, the configuration corresponding to the circuit blk0 may be the memory block BLK0 and the configuration corresponding to the circuit blk1 may be the memory block BLK1, and the different block addresses may be allocated to these two memory blocks BLK0 and BLK1.
In the semiconductor memory devices according to the fourth embodiment and the fifth embodiment as well, the common string address may be allocated to the string units SU0a, SU0b, SU5a, and SU5b or the different string addresses may be allocated. Similarly, the common string address may be allocated to the string units SU1a, SU1b, SU6a, and SU6b, the string units SU2a, SU2b, SU7a, and SU7b, the string units SU3a, SU3b, SU8a, and SU8b, and the string units SU4a, SU4b, SU9a, and SU9b, or the different string addresses may be allocated.
In the semiconductor memory devices according to the fourth embodiment and the fifth embodiment as well, similarly the semiconductor memory device according to the second embodiment, the configurations corresponding to the circuits blk0a, blk0b, blkla, and blklb may be the four different memory blocks, and the different block addresses may be allocated to these four memory blocks.
In the semiconductor memory devices according to the first embodiment to the fifth embodiment, for example, as described with reference to
However, for example, as illustrated in
The chip CM includes a semiconductor substrate 600, a memory cell array layer LMCA' disposed below the semiconductor substrate 600, a plurality of wiring layers disposed below the memory cell array layer LMCA’, and a bonding electrode layer MPM. Note that
The semiconductor substrate 600 is, for example, a semiconductor substrate made of P-type silicon (Si) containing P-type impurities, such as boron (B). On a surface (a lower surface) of the semiconductor substrate 600, an N-type well region 611 containing N-type impurities, such as phosphorus (P), P-type well regions 612 containing P-type impurities, such as boron (B), a semiconductor substrate region on which the N-type well region 611 or the P-type well region 612 is not disposed, and an insulating region 600I of, for example, silicon oxide (SiO2) are disposed. The P-type well region 612 may be disposed in, for example, the region corresponding to the conductive layer 112 (
The memory cell array layer LMCA' is basically configured similarly to the memory cell array layers LMCA according to the first embodiment to the fifth embodiment. However, the memory cell array layer LMCA’ does not include the conductive layer 112, 312, or 512. The upper ends of the semiconductor columns 120 in the memory cell array layer LMCA’ are connected to the P-type well regions 612 of the semiconductor substrate 600.
The bonding electrode layer MPM includes a plurality of bonding electrodes PI. These plurality of bonding electrodes PI are, for example, electrically connected to at least one of the configurations in the plurality of chips CM and Cp. The plurality of wirings m0 may include, for example, a stacked film of a barrier conductive film, such as titanium nitride (TiN) and tantalum nitride (TaN), and a metal film, such as copper (Cu), or the like.
The chip Cp includes the semiconductor substrate 100, the transistor layer LTR disposed above the semiconductor substrate 100, a plurality of wiring layers disposed above the transistor layer LTR, and a bonding electrode layer MPP disposed above these plurality of wiring layers. Note that
The bonding electrode layer MPP includes the plurality of bonding electrode PI similarly to the bonding electrode layer MPM.
The chip CM and the chip Cp are connected via the plurality of bonding electrodes PI. The configuration in the chip CM and the configuration in the chip Cp are electrically connected via the plurality of bonding electrodes PI.
As illustrated in
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms: furthermore, various omissions, substitutions and changes in the form of the methods and systems described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.
Claims
1. A semiconductor memory device comprising:
- a substrate that includes a first region and a second region arranged in a first direction and a third region disposed between the first region and the second region;
- a plurality of word lines extending in the first direction across the first region, the second region, and the third region, the plurality of word lines being arranged in a second direction intersecting with the first direction;
- a first select gate line that is disposed in the first region and farther from the substrate than the plurality of word lines;
- a second select gate line that is disposed in the first region and closer to the substrate than the plurality of word lines;
- a first semiconductor layer disposed in the first region, the first semiconductor layer extending in the second direction and being opposed to the plurality of word lines, the first select gate line, and the second select gate line;
- a first bit line extending in a third direction intersecting with the first direction and the second direction, the first bit line being disposed at a position overlapping with the first semiconductor layer viewed in the second direction;
- a third select gate line that is disposed in the second region and farther from the substrate than the plurality of word lines;
- a fourth select gate line that is disposed in the second region and closer to the substrate than the plurality of word lines;
- a second semiconductor layer disposed in the second region, the second semiconductor layer extending in the second direction and being opposed to the plurality of word lines, the third select gate line, and the fourth select gate line;
- a second bit line extending in the third direction, the second bit line being disposed at a position overlapping with the second semiconductor layer viewed in the second direction; and
- a word line contact electrode disposed in the third region, the word line contact electrode extending in the second direction and being connected to one of the plurality of word lines.
2. The semiconductor memory device according to claim 1, further comprising:
- a first transistor electrically connected to the first select gate line;
- a second transistor electrically connected to the second select gate line;
- a third transistor electrically connected to the third select gate line; and
- a fourth transistor electrically connected to the fourth select gate line.
3. The semiconductor memory device according to claim 1, further comprising:
- a first contact electrode disposed in the third region, the first contact electrode extending in the second direction and being connected to the first select gate line;
- a second contact electrode disposed in the third region, the second contact electrode extending in the second direction and being connected to the second select gate line;
- a third contact electrode disposed in the third region, the third contact electrode extending in the second direction and being connected to the third select gate line; and
- a fourth contact electrode disposed in the third region, the fourth contact electrode extending in the second direction and being connected to the fourth select gate line.
4. The semiconductor memory device according to claim 1, further comprising
- a source line connected to the first semiconductor layer and the second semiconductor layer.
5. The semiconductor memory device according to claim 1, further comprising a control circuit configured to perform a first erase operation by:
- applying a first voltage to the first select gate line;
- applying a second voltage to the second select gate line;
- applying a third voltage to the third select gate line; and
- applying a fourth voltage to the fourth select gate line, wherein
- the first voltage is smaller than the third voltage, and
- the second voltage is smaller than the fourth voltage.
6. The semiconductor memory device according to claim 5, further comprising
- a source line connected to the first semiconductor layer and the second semiconductor layer, wherein
- the control circuit configured to perform the first erase operation by: applying a first erase voltage larger than the first voltage and the second voltage to the first bit line; and applying a second erase voltage larger than the first voltage and the second voltage to the source line.
7. The semiconductor memory device according to claim 1, further comprising:
- a first source line connected to the first semiconductor layer; and
- a second source line connected to the second semiconductor layer.
8. The semiconductor memory device according to claim 1, further comprising a control circuit configured to perform a first erase operation by:
- applying a first voltage to the first select gate line;
- applying a second voltage to the second select gate line;
- applying a third voltage to the third select gate line; and
- applying a fourth voltage to the fourth select gate line, wherein
- the first voltage is larger than the third voltage, and
- the second voltage is larger than the fourth voltage.
9. The semiconductor memory device according to claim 8, further comprising:
- a first source line connected to the first semiconductor layer; and
- a second source line connected to the second semiconductor layer, wherein
- the control circuit configured to perform the first erase operation by: applying a first erase voltage larger than the first voltage and the second voltage to the first bit line; applying a fifth voltage smaller than the first erase voltage to the second bit line; applying a second erase voltage larger than the first voltage and the second voltage to the first source line; and applying a sixth voltage smaller than the second erase voltage to the second source line.
10. The semiconductor memory device according to claim 1, wherein
- the substrate includes: a fourth region farther from the third region than the first region; and a fifth region farther from the third region than the second region, and
- the semiconductor memory device includes: a fifth select gate line that is disposed in the fourth region and farther from the substrate than the plurality of word lines; a sixth select gate line that is disposed in the fourth region and closer to the substrate than the plurality of word lines; a third semiconductor layer disposed in the fourth region, the third semiconductor layer extending in the second direction and being opposed to the plurality of word lines, the fifth select gate line, and the sixth select gate line; a third bit line extending in the third direction, the third bit line being disposed at a position overlapping with the third semiconductor layer viewed in the second direction; a seventh select gate line that is disposed in the fifth region and farther from the substrate than the plurality of word lines; an eighth select gate line that is disposed in the fifth region and closer to the substrate than the plurality of word lines; a fourth semiconductor layer disposed in the fifth region, the fourth semiconductor layer extending in the second direction and being opposed to the plurality of word lines, the seventh select gate line, and the eighth select gate line; and
- a fourth bit line extending in the third direction, the fourth bit line being disposed at a position overlapping with the fourth semiconductor layer viewed in the second direction.
11. The semiconductor memory device according to claim 10, further comprising:
- a fifth transistor electrically connected to the fifth select gate line;
- a sixth transistor electrically connected to the sixth select gate line;
- a seventh transistor electrically connected to the seventh select gate line; and
- an eighth transistor electrically connected to the eighth select gate line.
12. The semiconductor memory device according to claim 10, wherein
- the substrate includes: a sixth region farther from the third region than the fourth region; and a seventh region farther from the third region than the fifth region, and
- the semiconductor memory device comprises: a fifth contact electrode disposed in the sixth region, the fifth contact electrode extending in the second direction and being connected to the fifth select gate line; a sixth contact electrode disposed in the sixth region, the sixth contact electrode extending in the second direction and being connected to the sixth select gate line; a seventh contact electrode disposed in the seventh region, the seventh contact electrode extending in the second direction and being connected to the seventh select gate line; and an eighth contact electrode disposed in the seventh region, the eighth contact electrode extending in the second direction and being connected to the eighth select gate line.
13. The semiconductor memory device according to claim 10, further comprising
- a source line connected to the third semiconductor layer and the fourth semiconductor layer.
14. The semiconductor memory device according to claim 10, further comprising:
- a first source line connected to the first semiconductor layer;
- a second source line connected to the second semiconductor layer;
- a third source line connected to the third semiconductor layer; and
- a fourth source line connected to the fourth semiconductor layer.
15. The semiconductor memory device according to claim 1, further comprising:
- a plurality of first memory cells disposed between the first select gate line and the second select gate line;
- a plurality of second memory cells disposed between the third select gate line and the fourth select gate line; and
- a control circuit configured to perform a first erase operation corresponding to an input of a first command set, wherein
- the first command set includes information to designate any one of the plurality of first memory cells or the plurality of second memory cells.
16. The semiconductor memory device according to claim 15, further comprising:
- a first memory block that includes the plurality of first memory cells; and
- a second memory block that includes the plurality of second memory cells.
17. The semiconductor memory device according to claim 10, further comprising:
- a plurality of first memory cells disposed between the first select gate line and the second select gate line;
- a plurality of second memory cells disposed between the third select gate line and the fourth select gate line;
- a plurality of third memory cells disposed between the fifth select gate line and the sixth select gate line;
- a plurality of fourth memory cells disposed between the seventh select gate line and the eighth select gate line; and
- a control circuit configured to perform a first erase operation corresponding to an input of a first command set, wherein
- the first command set includes information to designate any of the plurality of first memory cells, the plurality of second memory cells, the plurality of third memory cells, or the plurality of fourth memory cells.
18. The semiconductor memory device according to claim 17, further comprising:
- a first memory block that includes the plurality of first memory cells;
- a second memory block that includes the plurality of second memory cells;
- a third memory block that includes the plurality of third memory cells; and
- a fourth memory block that includes the plurality of fourth memory cells.
Type: Application
Filed: Mar 15, 2022
Publication Date: Feb 23, 2023
Patent Grant number: 12125542
Applicant: KIOXIA CORPORATION (Tokyo)
Inventors: Wataru MORIYAMA (Yokohama), Hayato KONNO (Yokohama), Takao NAKAJIMA (Yamato), Fumihiro KONO (Yokohama), Masaki FUJIU (Yokohama), Kiyoaki IWASA (Yokohama), Tadashi SOMEYA (Edogawa)
Application Number: 17/695,529